An apparatus or tool for bending a valve stem through the use of a roller or roller-like tool element with the tool being movable relative to a stationary work portion of the apparatus during deformation.
Conventional truck inner tube manufacturing processes generally require that the valve stem member remain in straight configuration, normal to the inner tube surface, until after the vulcanization process has been carried out.
The manufacturers of inner tubes for use in radial truck tires have to identify such tubes by some form of marking or indicia to be certain that they are properly used. While a plastic ferrule or a metal ring may be attached to a valve stem or a red stripe or similar marking may be painted on the stem, to so identify their use, the most permanent type or identification is to emboss the word--radial--on the valve stem.
The embossing or imprinting of the word--radial--has, in many instances, been carried out as manual operation wherein a metal die is placed upon the valve stem and then struck with a hammer. In other instances the metal die is mounted in a device whereby all letters or the word--radial--are simultaneously imprinted on the valve stem. In such instances the soft brass body of the valve stem may be bent or distorted during such printing, often to the extent the inner tube-valve stem assembly must be rejected.
In prior art devices inner tube valve stems have been bent by manual-type bending devices such as illustrated in the U.S. Pat. Nos. to Breer 1,879,869 dated Sept. 27, 1932 and Boyer et al 2,565,646 dated Aug. 28, 1951. In said prior art, manually-operated devices, the bending of valve stems is often very inconsistent as regards the bending angle and the bending location. Such devices produced valve stems with bends that were subjected only to visual inspection which resulted in the operations being carried out on somewhat of a trial and error basis.